Design and Verification of a Charge Pump in Local Oscillator for 5G Applications

Abstract

A charge pump (CP) that has low current mismatch to reduce the locking time of the Phase-Locked Loop (PLL) is proposed. The design is promising in 5G applications with the capabilities of fast settling and low power consumption. In this design, a charge pump architecture consists of an operational power amplifier (OPA), switches, three D flip-flops (DFFs) and passive devices. A phase error compensation technique is introduced in the charge pump to reduce the locking time. The current mismatch, which is mainly due to the leakage current, is below 1% for a large output voltage headroom of 84% of the supply voltage. An 18.4% reduction in the settling time is realized by the proposed design.